Towed vehicles, such as trailers, have brake signals that operate based on the braking signals of the towing vehicle. As is well known in the art, the braking signals of the towing vehicle are electrically connected to the braking system of the towed vehicle, such as via an electrical adapter, or the like. Typically, the signaling system of the towing vehicle has a signal lamp and a brake lamp that are operated by at least two separate filaments. However, most trailer signal systems usually combine the turn and brake signals into a single lamp with a single filament. Accordingly, an adapter or circuitry is often required in order to interface the signal system of the towing vehicle with the signal system of the towed vehicle or trailer.
Older model towing vehicles, such as pickup trucks, typically use a switch on the brake pedal to activate the brake lights. The switch is configured to send a signal, such as a 12 volt signal, to the vehicle's braking system or light controls. A towed vehicle may interface with the light signals of the towing vehicle, either directly or through a converter, to provide signals to the lights of the towed vehicle.
Trailer brake controllers are sometimes after-market devices that are designed to interface with the braking system of a towing vehicle and provide braking signals and light signals to a towed vehicle. Such trailer brake controllers commonly include a manual control to apply the brakes of the towed vehicle. When such action is taken, the lights of the towed vehicle must be activated. To activate the lights, trailer brake controllers are often configured to apply a voltage to the signal wire of the brake pedal switch. As described above, this signal activates the towing vehicle brake lights which in turn activates the towed vehicle brake lights. The towed vehicle brake lights are commonly the turn-signal lights activated together.
Newer model towing vehicles have replaced the brake pedal switch with a pedal position sensor. The pedal position sensor does not use the same 12 volt signal that was previously used with the pedal switch, but instead uses a signal that lacks the low impedance and voltage to drive the stop lamp input of the trailer brake controller. The sensor signal is then used as an input into a controller on the towing vehicle. This new design poses a problem for brake controllers, in that they are no longer able to receive the stop lamp signal when the towing vehicle brakes are applied.
In addition, on older model vehicles, the 12 volt signal from the pedal was able to be used to drive the brake lights on the towing vehicle directly, and therefore was able to also drive the trailer lights through a relay output. However, on newer model vehicles the pedal position sensor does not provide an adequate output to drive the lights and is not readily accessible. This new design poses a problem for brake controllers, in that they are no longer able to communicate the appropriate signal when the manual brake controls are applied.
Some towing vehicle manufacturers have provided an alternate access point to the stop lamp input signal. However, this output may not have the low impedance required to drive the stop lamp input of the brake controller. In addition, the alternate access point does not provide any means for the brake controller to drive the towing or towed vehicle brake lights.
In certain jurisdictions, alternative wiring and lighting systems are used to signal trailer braking. For example, in some countries, the trailer vehicle brake lights include both an amber light to indicate a turn signal and a red light to indicate a stop signal. Therefore, it is further required that a converter must be capable of outputting signals to drive both the turn signal light and the stop signal light on each side of the trailer.
Therefore, an improved solution is needed.